The key of each crud_objects child object should correspond to the resources property which uniquely identifies rows in this table. This is not strictly required, but you should typically specify a key unless there is no identifying resource in a table.

In the NIM Studio, your Primary keys should correspond to the keys specified here.

Example JSON:

"key": "id",
"resources": {
	"id": "string*",
	"primaryEmail": "string*"